63 valiant wagon 170/pushbutton 3 spd, the seal that the parking brake cable enters in the rear of trans is leaking(gasket is split), is it readily available and if so where?

I would try bulkparts.com They seem to have most everything and are inexpensive. I think they have a minumum purchase policy. You may just want to get an overhaul gasket and seal set, they are not that much.

Suggest getting your early-Torqueflite seals and parts from Pat Blais, tflitepatty@verizon.net . Pat is very knowledgeable about these transmissions and can save you a lot of "oops, not quite the right part" or "oops, have nine out of the eleven parts I need" grief.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

thanks to Anotherslant and slant six dan for your help!!! Will contact said people.